The Dynamical Theory of Gases

MORE than eleven years have elapsed since the first edition of this work was-reviewed in NATURE (April 27, 1905). Most of the pioneers of the attempted rigorous mathematical theory hav passed away, and the attempt to reconcile Boltzmann's minimum theorem with the properties of an aggregate of perfectly reversible units may be said to have been abandoned. On the other hand, the recently developed quantum hypothesis has, to some extent, had the opposite effect of leading us to believe that something more than the equations of reversible dynamics is needed to account for the phenomena of Nature. Equi-partition may be characteristic of molecular systems, but the celestial universe shows no tendency towards Maxwell's law, and would,probably refuse to obey it even if started according to this distribution.The Dynamical Theory of Gases.By J. H. Jeans. Second edition. Pp. vii + 436. (Cambridge: At the University Press, 1916.) Price 16s. net.